It is known to provide a decoupling mechanism on an accessory, such as an alternator, that is driven by a belt from an engine in a vehicle. Such a decoupling mechanism, which may be referred to as a decoupler, permits the associated accessory to operate temporarily at a speed that is different than the speed of the belt. For example, when there is a sudden stoppage of the belt when the belt was running and driving rotation of the alternator shaft, the decoupler permits the alternator shaft to continue rotating temporarily as a result of inertia until it decelerates to a stop as a result of drag, thereby reducing the stress on the alternator shaft. As another example, the decoupler permits the alternator shaft to rotate at a relatively constant speed even though the crankshaft from the engine undergoes a cycle of decelerations and accelerations associated with the movement of the pistons.
Such decouplers are valuable additions to the powertrain of the vehicle. However, there is a continuing need to reduce their cost, to improve their operating life, to reduce their complexity and to simplify their manufacture. It would thus be beneficial to provide a decoupler that addresses one or more of these continuing needs.